Flat plywood. Leveling plywood step by step description. Leveling a wooden floor with plywood on a crate

Leveling the floor with plywood has gained immense popularity due to the simplicity of the work performed and the availability of materials. Particularly popular is the leveling of a wooden floor with plywood 4 mm thick, since rather large sheets are used to perform the work, the installation of which is carried out quickly, efficiently and with virtually no waste.

It is not only durable and reliable, but also moisture resistant material that has passed special treatment and therefore used for installation of floors in rooms with high humidity.

Before you level the floor with plywood, you need to take care of right choice the most suitable sheets. There are several ways to do the work yourself, and for each method choose plywood that meets certain requirements. So, for example, 4 mm sheets are in demand when laying several layers of the selected material during the preparation of the floor surface for the installation of the finish coating.

The thickness of the plywood sheets used for leveling the surface must correspond to the thickness of the floor covering.

When thinking about how to level a wooden floor with plywood without the participation of specialists, it is worth paying attention to the choice of sheets, refusing to use chipboard. This is due to the fact that chipboard will repeat all the differences over time, and the prepared floor surface will not meet the requirements.

It is advisable to use materials without formaldehyde resins

Another one important feature- brand of material. FK is plywood made without the use of phenol-formaldehyde resins. It does not pose a danger to the consumer and does not emit fumes that are harmful to the health of others.

It is successfully used as a material for leveling the floor with plywood with your own hands. Such sheets are easy to cut, easy to install and process.

Rooms can be lined with 10 cm thick flooring

When choosing canvases for laying on top of a wooden floor in a living room, you should pay attention to the markings that display all the features of plywood. So, for example, for work in rooms, you can use sheets whose thickness is at least 10 mm.

To assemble high-quality flooring, you can purchase sheets of the second grade, which differ in that dents, cracks, and small knots or scratches can be found on their surface. The total percentage of damage does not exceed 5% of the entire surface of the canvas.

Another icon that indicates the quality of plywood processing is NSh or Sh1, Sh2. It testifies to the quality of the polishing performed:

NSh - unpolished sheets;
Ш1 - one-sided grinding;
Ш2 - double-sided grinding.

The E1 or E2 icon indicates what the free formaldehyde emission class is. According to experienced craftsmen, in order to perform floor leveling with plywood, it is necessary to purchase sheets of FK, Sh1, 2nd grade, class E1, choosing canvases whose thickness is from 10 to 12 mm.

Work order

When mounting plywood on old logs, check their condition

There are several options for installing plywood sheets in order to obtain a completely flat floor surface on which the final floor covering will be laid. Dry leveling with plywood is necessary if 1 square meter found differences in the height of the base, exceeding 4 mm.

Laminate, linoleum, parquet and even tiles can be used as such a coating. The order of the work depends only on what basis it is necessary to lay the sheets. To work on wooden floor two methods are popular.

Leveling the floor with plywood along the logs is carried out not only during the construction of a new house, but also during repair work in the old building. For work, you will need not only a screwdriver and self-tapping screws, but also a level and a laser level.

After the dismantling of the old floor is carried out, it will be necessary to check the logs and, if necessary, replace them with new ones, setting them strictly according to the level.

It is important to ensure that only dry wood is used during installation, so that under the logs there is a ventilation gap of at least 4 mm to the base of the floor. It is necessary to take care of high-quality sound and heat insulation.

Features of work performance

Fixation to the base is carried out using anchor bolts, after checking the horizon. If the old logs had to be completely removed, then the new ones are installed at a new horizontal level. How to level the floor top coat see in this video:

Dry bars are used as new logs. conifers tree. Another point of great importance is that plywood sheets are laid and fixed in such a way that the edge of the sheet does not hang freely, but lies firmly on the logs.

It is important that 4 sheets do not converge at one point

Laying is carried out so that 4 corners of four sheets do not converge at one point. This means that plywood is laid in a run. Between the canvases there is a gap of at least 2-3 mm, only self-tapping screws are used for fixing.

Starting laying from the middle of the room, we must not forget that the distance from the edge of the sheet to the wall should not be less than 2 cm. First, one strip is laid from one wall of the room to the opposite.

After that, taking into account all that has been said before, they begin laying the second strip. When purchasing self-tapping screws that will fix the leveling layer, you should choose their length correctly. This requires a thickness plywood sheet multiply by 4.

Leveling the floor with plywood without a lag is possible in cases where the differences in the base do not exceed 5 mm. The distance from the walls is at least 3 cm, the gap between the plates is at least 5 mm. This method allows you to put your floor in order without installing a support beam.

Small differences are evened out with a fine adjustment when fixing the plywood sheets to the floorboards.

Plywood will be an additional soundproofing layer

If necessary, the sheets are laid in several layers, and during the execution of these works it is worth taking care of the correct laying of the sheets. It is unacceptable to cross 4 butt joints in one place.

Leveling the concrete floor with plywood has become widespread due to the ability to equip additional thermal and sound insulation. All work is carried out after the construction of the lag, between which insulation will be laid. Before starting work, it is necessary to check the condition of the subfloor and eliminate any defects found in the screed in the form of cracks, depressions, bumps.

The cleaned surface is treated with a primer mixture and, after it dries, the installation of waterproofing is started, on top of which the crate is assembled and fixed.

After the entire structure is brought to a horizontal level, you can start laying plywood sheets. We must not forget about the need to create deformation gaps from 5 to 10 mm. To learn how to level curved floors with plywood, see this video:

Their absence will lead to the fact that the new floor will soon go in "waves". The distance between the screws is from 20 to 25 cm, the distance from the walls is 2-3 cm.

It is better to drill all holes in plywood sheets in advance. This will make installation easier and faster. It is equally important to take care of creating ventilation in the underground. To do this, even before fixing the skirting boards, it is necessary to drill holes in certain places, which are covered with ventilation grilles. The main distinguishing feature of this leveling is the rise of the floor by only 3-5 cm, which slightly affects the height of the ceiling in the living room.

One of the repair operations quite often becomes floor leveling, for which they use various materials, including: self-leveling and cement-sand screeds, concrete, plywood and other materials that allow you to make the coating even and smooth, providing not only beauty, but also convenience, strength, durability.

One of the options for leveling the floor was the use of well-known plywood for this operation. Each material has its advantages and disadvantages, so if you decide to level the floor with it, you should familiarize yourself with the main characteristics of the product and its use.

Before leveling the floor with plywood, familiarize yourself with its features

The main advantages for this operation are considered to be:

small amount of time for its installation;
a fairly clean method that leaves a minimum amount of dust and debris;
especially effective when mounted on a wooden floor, since plywood has a relatively small weight and does not give a large load to the base;
ease of installation that does not require special skills and professional training.

As for the shortcomings of this material as a leveling agent, the following are noted among them:

the impossibility of using the "warm floor" system during installation;
a negative reaction to high humidity, which leads to a decrease in the quality of the material itself and the work performed;
work requires a material with a thickness of at least twenty-two centimeters, which leads to a significant increase in its cost;
for wet rooms, a moisture-resistant product is required, which is not cheap.

Quality will matter a lot waterproofing works especially in rooms with high humidity.

Plywood is relatively inexpensive and in a simple way floor leveling

How to buy plywood for floor leveling

Today, the building materials market is replete with various offers, and their wide choose is not always a blessing, as it puts home master, especially if he has no experience or practical skills are small, at a standstill: what plywood to choose, what material and manufacturer to give preference to?

per grade;
compound;
sheet thickness;
water resistance.

The choice of material must be approached carefully

In this case, the last position for many may be decisive.

There is a large selection of plywood on sale, and you need to choose it correctly, and for this you need to familiarize yourself with the main characteristics and properties of the material.

	Advantages	Flaws
	Ecologically pure Suitable for home decoration	Susceptible to excess moisture
	Preferred for repair and construction work in dwellings	Direct contact with water is undesirable
	High level of moisture resistance
	High level of resistance to chemically aggressive environments	It is not advisable to use it in the underfloor heating system: when heated, harmful substances are released
	It is used in the arrangement of light sea and river vessels, due to special waterproof treatment	Not suitable for floor leveling
	Identical to BS	Water resistance is reduced compared to BS

Advice. When choosing plywood, you should pay attention to the orientation of the fibers: along the length or width. This moment is taken into account when leveling the floor so that they lie against the main movement.

When laying, look at the direction of the fibers

How to level the floor with plywood on the logs with your own hands

You can level the floor by lags and without them. To carry it out, a material with a thickness of at least ten millimeters is required, while the number of layers in it does not matter. In total, the thickness of the stacked sheets should be from fifteen to eighteen millimeters.

Experts believe that laying the leveler along the logs is not difficult, so you can do it yourself.

For lag use a tree and metallic profile, while it is clear that the metal is much stronger, but it must be taken into account at what temperature it will be used: temperature indicators are of direct importance.

In order for the laying to be carried out efficiently and effectively, it is necessary that they be the same on the logs and the leveler. Therefore, when using plywood best material log will be a tree, better - if coniferous. The highest quality is larch, but it is very expensive.

You can level the floor by lags and without them

Before starting installation, it is necessary to carry out preparatory work.

cook necessary material for lag. It can be dry boards or timber at least two meters long. You need to buy them in advance and let them “lie down” in the room where the logs will be installed.
Treat the tree with an antiseptic to avoid damage by insects and rodents, and preparations for fire and bioprotection.

The next step will be the flooring of the black floor covering along the logs. At the same time, they are installed not with the help of a screed, due to fastenings on “linings” from scraps of timber and boards, under which linoleum or roofing material is laid. After that, a frame is formed, where the insulation and vapor barrier are laid, after which the plywood sheets are directly laid, pre-measured and cut into the right size.

Plywood will become great option for floor leveling

How to level the floor with plywood without lag

The advantages of leveling the floor with plywood along the logs are: no need to install a concrete screed, which saves money and time, as well as the simplicity and environmental friendliness of the method. It is possible to level the floor with plywood without a lag, while experts say that this operation is not at all complicated. Sheets are fixed in one of the following ways:

gluing;
regulation.

In the first case, you will need a special adhesive composition, which can be used if the floor has minor height differences and there is a concrete screed, which must be completely dry by the time of leveling. This method is simple and does not require significant time.

Regulation is considered a more complex method, so it is used much less often. The fastening of plywood sheets, which are laid in two layers, takes place on wooden blocks, which requires time and accuracy. But its use allows the structure to withstand significant loads, and the master - without much hassle in the future to dismantle and replace the old floor covering.

You can level the floor without a lag either with glue or regulation

Do-it-yourself leveling of a wooden floor with plywood

If the room has a wooden floor, then the best way leveling will use plywood. The installation technology of such a coating is not very difficult, so you can do it yourself. The order in which it is carried out is as follows:

padding;
screed manufacturing;
priming;
warming;
leveling the wooden floor with plywood.

Priming is a necessary procedure that allows you to get rid of cracks, chips, and even out the resulting potholes. Otherwise, the coating will not last long and begin to creak.

The screed, which is designed as a base for plywood, is made of concrete. After its complete drying, priming is carried out, i.e. base primer. With this procedure:

the surface of the base is cleaned, including from dust;
the base is impregnated with a primer made of the same material with which the plywood will be attached to the screed.

Then the insulation is laid, and on it - sheets of plywood marked for laying.

Plywood is great for leveling wood floors.

About pretreatment of plywood

In order for the leveled floor to last for a long time, you need to properly prepare the leveler.

When buying, you need to make sure that the plywood is dry and not warped: it will be difficult to work with deformed sheets. It should be stored not in the open air, but indoors at a temperature characteristic of this place.

Before laying, the sheets must be marked and cut (cut) in an appropriate way, taking into account not only the size of the room, but also the laying features: corners, columns, pipes, etc.

Then they are laid out on the floor so that the master is convinced that all measurements and cuts were made correctly. At the same time, one should not forget about the necessary gaps between the sheets, and especially near the walls: the sheet should not be butt with the wall.

After cutting and fitting, they are numbered, which greatly facilitates installation and does not lead to confusion, and are removed. Installation is carried out in small sections, slowly and efficiently.

Before starting work, the sheets must be measured and cut.

Plywood fixing methods

Plywood can be fixed during leveling different ways, due to the requirements for the operation:

gluing on a concrete floor;
regulation on hairpins;
installation on the frame;
wood flooring;
screwing sheets;
floor regulation.

Plywood can be laid different ways

Mounting plywood on adjustable studs

This method, using anchor rods, allows you to get rid of significant floor irregularities by adjusting the position of its surface. It happens like this:

grooves are prepared with a drill, the depth of which is half the thickness of the sheet;
a hole is drilled inside for a pin of a smaller diameter;
washers are inserted into the recesses;
marks are made for drilling holes in the floors, after which the sheet must be removed.

Anchor studs are fixed on the floor surface, with a screwed nut and washer, on which the prepared plywood sheet is laid and attached to the studs with nuts. The excess length of the anchors is removed by the grinder.

In this way, you can get rid of significant floor irregularities.

Leveling a wooden floor with plywood on a crate

One of the methods for leveling a wooden floor with plywood is to mount it on a crate. It is advisable to use it when preparing a floor covering for a laminate; for this is carried out:

dismantling of the old wooden covering on the logs;
their inspection, replacement of unsuitable for operation;
strengthening of the longitudinal bars with piping along the perimeter and control of horizontal laying;
installation of insulation and vapor barrier;
plywood flooring with joints on the support.

Laying on the crate is done in stripes. They are fastened in increments of twenty centimeters, taking into account the peculiarities of the architecture of the room, after which all the irregularities are processed with putty.

Installing plywood on battens is a popular floor leveling method.

Leveling concrete screed with plywood

This type of alignment is not difficult, but requires careful attention to the nuances of the operation, which can significantly affect the final result of the work.

To avoid problems with the floor covering after the work is completed, it is necessary to take into account that before laying the plywood on concrete base it must be ensured that the substrate is absolutely dry or that it meets the humidity standards at which work can be carried out.

Experts have found a simple and effective method determining the level of humidity on concrete pavement: part of it is covered plastic wrap and after some time, usually after two or three days, if the moisture content of the substrate is high, drops of moisture will appear on the film coating. This means that the temperature in the room will have to be raised, avoiding an increase in humidity.

Before leveling the concrete floor with plywood, make sure that the humidity in the room is low.

To protect plywood from moisture and low temperatures, it is usually treated with an antiseptic before installation.

Attention! To fix the nuts after adjustment, they must be treated with a thread lock, which will increase the strength of the floor fixing.

Video: Do-it-yourself floor leveling with plywood

Video: Leveling a curved floor with plywood

Many home craftsmen who decide to build housing with their own hands or simply start overhaul, at a certain stage of work they face the problem of uneven floors. In fact, leveling a concrete base is much easier than it might seem at first glance. And the most obvious option is to use plywood for this.

From this article you will learn how to level the floor under the laminate with plywood.

In the photo - a floor with laid plywood sheets.

About floor leveling

An uneven base is primarily a creak, deformation and destruction of the integrity of the floor covering, and, consequently, a significant reduction in its service life. Therefore, the repair of the floor must begin with its alignment.

Any, even the most durable flooring, needs a quality foundation. The most expensive parquet or the highest quality laminate flooring will not meet the stated specifications if it is laid on an unprepared base. Therefore, many home craftsmen are interested in the question: "How to level the floors with plywood?".

To date, this method of leveling the floor surface is the most affordable and popular, allowing you to create a high-quality base for the final coating in a short time. An alternative to this method is a concrete screed, but this process is longer, and the price of such work will be somewhat higher.

Types of floor leveling

You should use one of two main ways to carry out such work.

And if you know how to line walls with plywood, then you will not find anything new here:

When it comes to relatively even wood flooring, it is enough just to screw plywood sheets to it with screws. Remember to make sure that the plank floor is strong enough before doing this. Plywood must be at least 10 mm thick.
Another option - the floor on the logs. It is more time-consuming to work, but also more thorough and, unlike the previous method, allows you to achieve perfect evenness of the floor, preparing the base for laying any type of coating.
On such a basis can be laid:
- carpet,
- parquet,
- linoleum, (see also)
- laminate,
- tile,
- as well as any other material.

Preparation for work

Before starting work, it is necessary to carefully prepare the base. Concrete is a material that is characterized by high humidity, therefore, before starting work, be sure to make sure that the humidity level in the room does not exceed allowable norms. In addition, be sure to clean the surface of dust and dirt.

Advice!
To test the concrete base for dryness, you can cover a small area with plastic wrap and press something heavy around the edges.
Check after three days inside polyethylene - if condensation appears on its surface, then this indicates high humidity grounds.

In order to avoid damage to plywood sheets under the influence of low temperatures and moisture, you should cover them with an antiseptic, which will help prevent the appearance of fungus and mold.

Material selection

If you do not know which plywood to level the floor with, then you should pay attention to plywood sheets of the 4th category. They are more affordable in terms of cost, in addition, they are treated with special compounds that protect against moisture and pests.

There is also a higher quality material. It does not have chips, defects and knots, therefore it can be successfully used for final coatings (for example, the final wooden floor).

If you have old plywood sheets, then they can also be used, since plywood is easy to level - just put it under a press.

We carry out installation

In practice, leveling a floor is as easy as leveling plywood walls.

To do this, you will need the following tools:

Screwdriver.
Perforator.
Hammer.
Roulette (from 3 meters).
Electric jigsaw.
Liquid or laser level.

The installation instructions include the following steps:

Prepare the base as described above. Clean the concrete screed from dust and dirt, dry it thoroughly.
Using the level, it is necessary to mark the floor boundary. Do this throughout the room.
Prepare the lags. Logs can be bought at any hardware store. Optimal parameters the log is 40 by 100 mm in cross section.

Advice!
When choosing logs, pay attention to the fact that they are well dried.

Prepare joist pads. These are wooden boards about 15 cm wide, 20 cm long and 2.5 cm thick.
We lay the lag across sunlight with a step of 40-50 cm.

Advice!
Between the lags you can lay plates thermal insulation material.
Thus, you will not only insulate, but also soundproof your floor.

Do not lay logs close to the walls. It is necessary to leave a gap of 2-3 cm in order to avoid deformation of the material due to seasonal changes.
In the process of laying, make sure that the logs correspond to the pre-marked floor height.. In uneven places, adjust their height by substituting wooden wedges.

After the logs are laid, you can start laying the transverse bars.
The crate is ready. Now you can start fixing the plywood to the floor. The sheets should be dried in advance if they were brought from the street, and then cut using an electric jigsaw into 75 by 75 cm squares. (See also the article) Screw such squares to the logs so that there is a small gap between them (2-4 cm). Otherwise, the floor may begin to creak over time.

Conclusion

This method of leveling the floor is very effective and economically beneficial. (see also) In addition, it is easy to perform, and it will not be difficult for any master to complete all the steps of a simple instruction.

In the presented video in this article you will find additional information on this topic.

Plywood floor repair

Experts identify the 4 most popular plywood floor leveling schemes:

the easiest method is without setting the lag. Installation of supports is not necessary, because the bumps of the curved floorboards act as supports. It is necessary to make indents from the walls by 2 cm. Plywood sheets are mounted after 0.5 cm. Before installation, the material must be left indoors for several days so that it gets used to the conditions. Do not forget about the mandatory treatment with an antiseptic. In addition to plywood for this work, you can take sheets of DSP or GVL
a grid of longitudinal logs and transverse boards. This method involves the creation of a frame from longitudinal logs and crossbars laid in the same horizontal plane. Logs are attached 3 cm from the wall. Sheets of plywood are screwed on top of these logs.
mini log system This method is convenient to use if there are significant differences of several centimeters. During this work, battens and wooden linings are installed in order to create a single support system for the plywood. It is necessary to carry out accurate engineering calculations, without which this task cannot be completed. First of all, it is worth making a fitting, and then, according to the marks indicated on the floor, for a long time and carefully calculate the dimensions of each supporting element. In this system, all elements supporting structure will have different sizes.
frame made of turned supports. With this scheme, mounted individual supports cut from board or plywood. The thickness of the supports is different, depending on the height of the floor. The result of the work is a solid mesh - with a size of squares from 30 to 45 cm, on which plywood is laid. Due to the fact that such a design is not very reliable, the cell pitch should be smaller than in previous versions.

Quite a new and original method leveling a wooden floor with plywood can be called puttying its surface with a solution that is made from small sawdust and PVA glue. This is a non-standard screed made of PVA-sawdust putty, on top of which are placed thin sheets plywood (5-8 mm). The advantage of this method is significant cost savings, and the disadvantages include the duration of the implementation of the method. Such a putty will dry for about two days, and if several layers are needed, then the drying time is doubled.

Work technology

How to lay plywood on the floor? Installation can be divided into three stages:

plywood calculation
fastening lags
fastening plywood sheets.

Before starting work, you need to measure the perimeter of the room and cut the plywood. Remember that you need to leave 1 cm from the wall, as well as 0.5 cm between sheets of plywood. Without such gaps, deformation of the plywood may occur as a result of fluctuations in humidity and temperature levels. At the end of the cut, it is necessary to inspect the ends of the plywood in detail. If defects or delaminations are found, discard such material.

What are lags? The lag is a plywood board, 3-4 cm wide. They are mounted strictly according to the outlines. They are attached with glue or screws. At each stage of work, you need to check the evenness of all components.

When the installation of the lag is completed, you can start laying plywood sheets. They are attached to self-tapping screws with plastic dowels. To avoid cracking when driving dowels, you need to drill holes. When all construction works finished, you need to clean the room and cover the plywood with several layers of varnish.

With the help of such techniques, you can easily level even the most curved floor. A parquet board or laminate will ideally lie on the resulting base. And do not forget about the ventilation of the underground. At the end finishing works must be drilled in the baseboard ventilation holes at the designated points. The openings are covered with ventilation grilles.

The use of plywood is rightfully considered an economical and well-established way of leveling the floor surface in wooden buildings. Dry screed with sheet material does not require incredible labor costs, does not require significant financial investments. There are no tangible technological breaks in the process that delay finishing. But there are nuances that an independent performer needs to know about. Before proceeding with the planned repair, you should figure out how to level the wooden floor using plywood sheets in order to avoid unwanted and not at all cheap alterations.

How to create an impeccably flat surface using factory adjustable systems, the videos will demonstrate in great detail. The video is aimed at owners of city apartments with concrete floors.

Basically, the method of installing adjustable logs with plywood or plywood sheets with anchor posts on wooden base does not differ from the scheme of their arrangement over cement slabs.

If the owner of a country bath has a surplus Money, he may well use ready-made adjustable kits. Alignment in the rest room, in the billiard room or in the dressing room will be carried out quickly and without much effort. However, we certainly will not classify adjustable plywood and logs as cheap methods. Let's explore budget options.

Methods and techniques for leveling plywood

The choice of the optimal technology for leveling a wooden floor with plywood determines the condition of the floors and the degree of deviation of the “relief” of the surface from the standard specified by the building requirements:

with a difference in height levels of 2 mm, found on a plot of 1 m 2, even for laying linoleum, which is extremely sensitive to deviations, alignment is not required. A sufficient measure would be processing with acrylic sealant or puttying with a home-made mixture of moistened sawdust and PVA glue;
with uniform deformation of properly laid floorboards with a difference in height levels of 5 mm, leveling the floor with plywood can be done by attaching the sheets directly to the plank floor;
height differences of more than 1 cm, but not more than 8 cm, require the creation of point or tape supports. In fact, the process consists in arranging a crate from a bar or from cobs that replace solid logs, for the manufacture of which thick plywood or board is used.

Proper laying means that builders alternated boards with different directions drawing of annual rings of wood according to technological requirements. This means that bulges-humps or concavities-boats on the floor appeared through one or two boards.

If it is not possible to level the wooden floor with your own hands without problems due to too large height fluctuations, the structure must be dismantled and built from new lumber. Such serious deviations certainly have no less serious reasons.

It is important to note that dry leveling plywood can only be used if technical specifications gender no complaints.

How to determine the difference in height?

A laser device is an excellent thing, but a two-meter level gauge will be more effective as a measuring tool in this case. It makes it easier to study the surface. It is necessary to mark the points in the corners of the room being repaired, to find and designate the centers of the floor and wall interface lines, the center of the room. Having divided the room into peculiar segments, it is necessary to examine each section. Evaluation of the recorded results will draw a picture of the upcoming repair.

Regardless of the range of upcoming work, it is imperative to carry out an audit and repair of the foundation. It is necessary to eliminate the creak, update the fasteners, replace the damaged elements, check the performance of the "underground" communications.

Method #1 - The "easiest" without installing a lag

Before laying plywood, it is necessary to provide the opportunity to "get used" to the conditions of the upcoming service. The material intended for arranging a regularly heated room needs to stand on the edge for a couple of days where it will be laid. In a room not spoiled by permanent, dampened warm water sheets should stand for at least a day.

All wood floor elements and dry screed materials based on wood veneer or fibers are pre-treated with an antiseptic.

by the most the easy way leveling the floor with plywood is considered a method without installing a lag. Installation of the support beam is not required, since its function will be adequately performed by the evenly distributed tubercles of the curved floorboards. In addition to plywood, DSP or GVL boards are suitable for such alignment.

It is pointless to level the wave-like deformed fiberboard floor. During operation, the material will shrink and repeat all the notches with tubercles of the rough base.

For a plank floor with a floorboard width of up to 20 cm, each of which is “swollen” evenly, we will buy plywood 8-10 mm thick. If a board with a width of more than 20 cm was used for flooring, and also if not every floorboard rests with a convex "hump" against a plywood sheet, sheet material will be required with a thickness of 18-20 mm.

The sequence of actions for leveling the subfloor with plywood:

Along the perimeter of the repaired floor, we will set the bosses to form a mandatory two-centimeter indent from the walls.
Plywood sheets are laid with a gap between them of 3-8 mm to cushion the movements caused by moisture fluctuations. When laying several rows, we imitate brickwork. That is, we place the plates of the next row with an offset to the plates of the previous one. There should not be a cruciform intersection of four butt welds at one point. Minimum size offsets - a quarter of the sheet, maximum half.
We fasten to the “crests” of the boardwalk at the points with the maximum height established during the preliminary survey. We try to distribute the attachment points evenly, focusing on the distances between the bulges identified as a result of measurements.

Holes for fasteners are recommended to be drilled in advance in two stages. First you need to use a drill, the size of which is equal to the diameter of the self-tapping screw. Then you need to make a hole with the diameter of the cap so that it can be completely sunk into the plywood sheet. The dowels along the perimeter of the plywood sheet should recede from the edge by at least 2 cm.

It is recommended to lay plywood sheets with one-sided roughness intended for subsequent laying of a finishing coating with the unsanded side up to improve the adhesion of the coating to the leveling layer. It is better to turn the sanded side if you plan to simply mask the screw heads with acrylic sealant, and open the plywood with varnish from above.

Method #2 - with a band support device

The technology consists in the construction of a crate of longitudinal logs and crossbars, exposed in one horizontal plane. Logs along the perimeter are located at a distance of 3 cm from the walls. The step of laying the longitudinal components of the structure being constructed frame system determines the size of the plywood sheet. Usually its values vary from 40 cm to half a meter.

Example - if the side is 152.5 cm, then the optimal distance between the axes, both the log and the crossbars, will be 48 - 50 cm. If the side is 122.0 cm, it is recommended to leave 37 - 40 cm between the axes of the support beam.

Step by step guide:

Let's start with an example. Let's lay out plywood without fastening, adhering to the standard scheme brickwork and providing gaps. Let's outline the outline of the plates, these lines will become guides for future marking the location of the lag. Don't forget to number the sample sheets.
According to the markings made on the floor, we first mount the logs along the walls. Optimal material for the device of a strip crate for plywood, a square beam with a side of 40 to 60 cm is considered, options are allowed. If it is undesirable and not necessary to raise the floor too much, logs can be made by cutting plywood into strips, or using second-class boards.
We install transverse jumpers with a step calculated according to the size of the sheet. They are attached to the lags with self-tapping screws, preferably using metal corners.
We set the logs and transverse elements vertically into a single plane according to the readings of the level gauge. Those who wish to figure out how to correctly level the surface of an old wooden floor should adhere to the requirements specified in SNiP number 3.04.01-87. According to this collection of standards, it is forbidden to drive wedges from the remnants of lumber under the logs. Alignment is carried out by adding sand, with minor deviations by lining roofing material or roofing felt. Most often, a single lag plane is achieved by placing wooden pads such as point supports under them.
After leveling, the log system is attached to the base with galvanized metal corners; it can be used to fix the dowel crate, the length of which is three times the thickness of the log.
We complete the alignment by laying and fastening plywood.

The space between the lag bars can be filled with additional insulation or a home-made screed made of wet sawdust mixed in half with PVA glue.

We apply a mixture with a consistency resembling thick sour cream in two or three layers and wait for it to completely harden for two days. In such cases, thinner plywood can be purchased for leveling.

Method #3 - Alignment with a mini-lag device

It is used to level floors with a slope and with significant height differences up to 8 cm. It consists in installing slats and wooden linings in order to create a single support system for plywood. Without an accurate engineering calculation, it will be extremely difficult for the contractor to cope with a very difficult task.

First you need to try on, and then, using the lines marked on the floor, carefully calculate the size of each supporting element. You need to calculate the height and select the dimensions very carefully, since all elements of the supporting structure will be different.

Method #4 - with a crate of point supports

The point method consists in installing separate pillars, cut from a board, OSB boards or all the same plywood. The thickness of the cob is selected in accordance with the difference between the created flat surface and real level. Ultimately support system should form a kind of grid that replaces the tape crate.

Since in terms of reliability and stability it is inferior to tape type, linings-covens are installed with a smaller step. You should get peculiar cells with imaginary squares of 30 cm for sheet material up to 14 mm thick, 45 cm for thick plywood.

And don't forget to ventilate the underground! After completing the separation and installation of the skirting board, it is necessary to drill ventilation holes in it at the previously existing points. Cover the openings with a ventilation grill.

Figured out the best way to line your wood floor with plywood? The point is small, it remains to prepare mentally and technically and begin to implement plans. Surely everything will turn out fine, because the repair procedure does not present any particular difficulties.